As is known, batch freezers currently used for producing handmade ice-cream comprise a substantially parallelepiped-shape outer boxlike housing; a cylindrical-shaped processing tub extending into the boxlike housing, from the front face of the housing, while remaining coaxial to a substantially horizontal reference axis; and a porthole-shaped closing door, which is hinged onto the front face of the boxlike housing so as to be able to rotate about a vertical axis, and being positionable at closing of the inlet of the processing tub.
The presently known batch freezers further comprise an inner cooling circuit which is able to bring and hold the processing tub and its content at a temperature lower than 0° C.; a mixing member which is rotably mounted within the processing tub so as to be able to uniformly mix the various ingredients during the ice-cream creaming process; and finally an electric motor able to drive into rotation the mixing member within the processing tub.
The mixing member is further designed so as to be able to scrape the inner cylindrical surface of the processing tub, and possibly also the bottom of the same tub, so as to prevent, during the creaming process, the high viscosity mixture formed within the processing tub from stably adhering to the side wall and to the bottom of the tub, thus compromising the quality of the produced handmade ice-cream.
Obviously, the closing door of the batch freezer must be designed so as to fluid-tightly close the inlet of the processing tub, and to successfully retain the mixture within the processing tub during the final steps of the creaming process, when viscosity and consistency of the mixture reach particularly high values.
In order to meet this purpose, in nearly all the currently marketed batch freezers, the closing door consists of a substantially discoidal-shaped plate made of metal material, which is hinged onto the front face of the housing as a porthole, and at the lower part is provided with a draining opening with a guillotine-like fluid-tight shutter, through which the ice-cream comes out at the end of the creaming process. A hopper for loading the ingredients is further realized on the upper part of the metal plate, which hopper directly communicates with the inside of the processing tub so as to be able to pour the ingredients into the processing tub when the plate abuts on the inlet of the tub and closes the latter.
Unfortunately the weight of the closing door of the currently marketed batch freezers is so high to make economically unfeasible the production of a machine in which the processing tub is arranged in a vertical position, on the top of the boxlike housing. In fact, in this configuration the closing door should rotate about a horizontally oriented articulation axis, thus forcing the user to apply a considerable physical effort whenever he wants to open and close the door.
Furthermore, the machine safety standards would make it necessary to equip the batch freezer with a series of safety systems capable of preventing, during opening or closing, the door from violently falling on the user's fingers causing potentially very severe physical injuries. The safety systems would lead to a considerable increase in the production costs of the machine.